XANTHENE DERIVATIVE COMPOUND HAVING HIGH REFRACTIVE INDEX AND (CO)POLYMER COMPRISING SAME

Abstract

The present disclosure relates to a xanthene derivative compound with a high refractive index and a manufacturing method therefor. More specifically, provided herein is a compound that has a xanthene-based complex cardo structure and a high refractive index and can be used as a monomer in optical resins requiring a refractive index of 1.7 or higher, and a (co)polymer and an optical lens manufactured therefrom. Given, the xanthene-based complex cardo structure of the compound maximally suppresses the fluidity of the molecular chains and can find applications in the production of resins with high glass transition temperature and excellent thermal stability.

Claims

1. A compound having a chemical structure of the following Chemical Formula 1: ##STR00032## wherein X, R.sup.1a, and R.sup.1b represent substituents; X is O, S, or SO.sub.2; m1 and m2 are each independently an integer of 0 to 4 (with a proviso that m1+m2 is an integer of 1 to 8), R.sup.1a and R.sup.1b are each selected from the substituents having the chemical structures of Chemical Formulas 1-1 to 1-3, below: ##STR00033## wherein, n1 and n2 are each independently an integer of 1 to 5, with a proviso that n1+n2 is 2 to 10; ##STR00034## wherein, n1 and n2 are each independently an integer of 1 to 5, with a proviso that n1+n2 is 2 to 10; and ##STR00035##

2. The compound of claim 1, wherein the compound has any one of the chemical structures of the following Chemical Formulas 2-1 to 2-3: ##STR00036## wherein, X is O, S, or SO.sub.2, and n is an integer of 1 to 5.

3. The compound of claim 1, wherein X is SO.sub.2.

4. The compound of claim 3, wherein the compound has the chemical structure of the following Chemical Formula 3-1 or 3-2: ##STR00037##

5. The compound of claim 1, wherein X is O.

6. The compound of claim 5, wherein the compound has the chemical structure of the following Chemical Formula 4-1 or 4-2 ##STR00038##

7. The compound of claim 1, wherein X is S.

8. The compound of claim 7, wherein the compound has the chemical structure of the following Chemical Formula 5-1 or 5-2: ##STR00039##

9. A (co)polymer, prepared from the polymerization components comprising: (a) the compound of claim 1; and (b) a diisocyanate compound or a polycarbonate precursor.

10. The (co)polymer of claim 9, wherein the diisocyanate compound is at least one selected from the group consisting of methylene diphenyl diisocyanate (MDI), p-phenylene diisocyanate (PPDI), tolylene-2,4-diisocyanate (2,4-TDI), tolylene-2,6-diisocyanate (2,6-TDI), xylylene diisocyanate (XDI), 1,5-naphthalene diisocyanate (NDI), hexamethylene diisocyanate (HDI), 4,4-methylene dicyclohexyldiisocyanate (H12MDI), 1,4-cyclohexane diisocyanate (CHDI), isophoroene diisocyanate (IPDI), and 1,3-bis(isocyanatomethyl) cyclohexane (H6XDI).

11. The (co)polymer, wherein the polycarbonate precursor is represented by the following Chemical Formula: ##STR00040## wherein, Rb1 and Rb2 are same or different and are each independently a halogen, a substituted or unsubstituted alkyl, or a substituted or unsubstituted aryl, and b1 and b2 are each independently 0 or 1.

12. An optical lens, comprising the (co)polymer of claim 9.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0133] FIG. 1 is a flow chart illustrating a synthesis method for a xanthene derivative compound according to a first embodiment of the present disclosure.

[0134] FIG. 2 is a flow chart illustrating a synthesis method for a xanthene derivative compound according to a second embodiment of the present disclosure.

[0135] FIG. 3 is a view showing optical properties of the polyurethane materials PU-1 to PU-4 synthesized in Example 4 in terms of refractive index.

[0136] FIG. 4 is a view showing optical properties of the polyurethane materials PU-1 to PU-4 synthesized in Example 4 in terms of transmittance.

[0137] FIG. 5 is a view showing thermal properties of the polyurethane materials PU-1 to PU-4 synthesized in Example 4, as analyzed by differential scanning colorimetry (DSC) and thermogravimetric analysis (TGA).

[0138] FIG. 6 is a view showing optical properties of the polycarbonate materials PC-1 to PC-4 synthesized in Example 5 in terms of refractive index.

[0139] FIG. 7 is a view showing optical properties of the polycarbonate materials PC-1 to PC-4 synthesized in Example 5 in terms of transmittance.

[0140] FIG. 8 is a view showing thermal properties of the polycarbonate materials PC-1 to PC-4 synthesized in Example 5, as analyzed by differential scanning colorimetry (DSC) and thermogravimetric analysis (TGA).

BEST MODE FOR CARRYING OUT THE INVENTION

[0141] Hereinafter, the present disclosure will be described in more detail through examples. These examples are only for illustrating the present disclosure in more detail, and it will be apparent to those skilled in the art that the scope of the present disclosure is not limited by these examples according to the gist of the present disclosure.

EXAMPLES

[0142] Unless otherwise stated, % used to indicate the concentration of a specific substance is (weight/weight) % for solid/solid, (weight/volume) % for solid/liquid, and (volume/volume) olo for liquid/liquid throughout the specification.

[Example 1] Synthesis of Novel Xanthene Derivative Compound 1

[0143] (1) Synthesis of 2,7-dimethoxyspiro[fluorene-9,9-thioxanthene]

##STR00020##

[0144] To a two-neck flask equipped with a thermometer and a stirrer was introduced (2-bromophenyl) thiobenzene (7.857 g, 29.6 mmol). Dry THF (15 ml) was added, followed by stirring. While the temperature was maintained at ?78? C., 1.5M nBuLi (18 ml) was dropwise added. At the same temperature, stirring was conducted for one hour. To a different two-neck flask equipped with a stirrer were fed 2,7-dimethoxyfluorenone (5.2 g, 21.8 mmol) and dry THF (70 ml) which were then stirred together. This mixture was introduced into the flask maintained at ?78? C. with the aid of a syringe. At the same temperature, stirring was conducted for one hour. Thereafter, the temperature was slowly increased to room temperature while stirring for 3 hours. The reaction mixture was subjected at a reduced pressure to extraction with chloroform and NaCl. The organic layer thus formed was isolated and left in a vacuum to obtain intermediate 1 (7.69 g, yield 83%).

[0145] In a two-neck equipped with a thermometer, a stirrer, and a condenser, intermediate 1 (7.69 g, 18 mmol) was stirred, together with acetic acid (70 ml) and 36% HCl (10 ml), at 80? C. for 10 hours. Neutralization of remaining HCl with NaHCO.sub.3 and water was followed by filtration. The solid thus filtered was extracted with chloroform and NaHCO.sub.3. The organic layer was dried in a vacuum and purified to afford compound 1 as a solid (7.15 g, yield 80%).

(2) Synthesis of Spiro[fluorene-9,9-thioxanthene]-2,7-diol

##STR00021##

[0146] To a two-neck flask equipped with a thermometer and a stirrer were introduced 2,7-dimethoxyspiro [fluorene-9,9-thioxanthene] (3 g, 7.34 mmol) and dichloromethane (60 ml, 0.12 M) which were then stirred. After the temperature was lowered to 0? C., 1.0 M in BBr.sub.3 dichloromethane (22 ml, 22.02 mmol) was dropwise added slowly. The mixture was stirred for 3 hours while the temperature was slowly increased to room temperature. Subsequently, the temperature was reduced to 0? C. and ice was introduced to quench BBr.sub.3, followed by extraction with dichloromethane and NaHCO.sub.3. The organic layer thus formed was isolated, dried in a vacuum, and purified to afford spiro[fluorene-9,9-thioxanthene]-2,7-diol as a solid (2.7 g, yield 97%, purity 99.8%).

(3) Synthesis of 2,2-(spiro[fluorene-9,9-thioxanthene]-2,7-diylbis(oxy))diethanol (FTX Synthesis)

##STR00022##

[0147] In a two-neck flask equipped with a thermometer and a stirrer were introduced spiro[fluorene-9,9-thioxanthene]-2,7-diol (2.5 g, 6.57 mmol) and DMF (13 ml), followed by stirring. Ethylene carbonate (1 ml, 15.77 mmol) and TBAF (0.2 ml, 0.2 mmol) were added and stirring was conducted at 150? C. for 3 hours. After completion of the reaction, the temperature was decreased to room temperature and extraction was conducted with chloroform and water. The organic layer thus formed was isolated, dried in a vacuum, and purified to afford 2,2-(spiro[fluorene-9,9-thioxanthene]-2,7-diylbis(oxy))diethanol as a solid (2.83 g, yield 92%, purity 99.6%).

(4) Synthesis of 2,7-bis(2-hydroxyethoxy)spiro[fluorene-9,9-thioxanthene]10,10-dioxide (FTXDO Synthesis)

##STR00023##

[0148] To a two-neck flask equipped with a thermometer and a stirrer were introduced 2,2-(spiro[fluorene-9,9-thioxanthene]-2,7-diylbis(oxy))diethanol (105 mg, 0.22 mmol) and dichloromethane (7 ml, 0.03 M). The temperature was reduced to 0? C. and mCPBA (101 mg, 0.44 mmol) was added. While the temperature was slowly increased to room temperature, stirring was conducted for 5 hours.

[0149] After completion of the reaction, extraction was conducted with dichloromethane and NaHCO.sub.3. The organic layer thus formed was isolated and concentrated. The concentrate was purified by column chromatography (eluents: ethyl acetate and hexane) to afford 2,7-bis(2-hydroxyethoxy)spiro[fluorene-9,9-thioxanthene] 10,10-dioxide as a solid (83 mg, yield 75%, purity 99.2%).

[Example 2] Synthesis of Novel Xanthene Derivative Compound 2

[0150] (1) Synthesis of 2,7-dibromospiro[fluorene-9,9-xanthene]

##STR00024##

[0151] In a two-neck flask equipped with a thermometer and a stirrer, 2,7-dibromofluorenone (30 g, 88.76 mmol) and phenol (83 g, 887.6 mmol) were stirred together. Then, methanesulfonic acid (24 ml, 355.04 mmol) was added and stirring was conducted at 150? C. for 12 hours. After completion of the reaction, the reaction mixture was cooled to room temperature and subjected to extraction with chloroform, NaHCO.sub.3, and NaCl. The organic layer thus formed was isolated, concentrated in a vacuum, and purified to afford compound 1 as a solid (33.28 g, yield 76.5%, purity 99.8%).

(2) Synthesis of 2,7-dimethoxyspiro[fluorene-9,9-xanthene]

##STR00025##

[0152] In a two-neck flask equipped with a thermometer, a stirrer, and a condenser, compound 1 (1 g, 2.039 mmol), CuI (1.55 g, 8.159 mmol), and dry DMF (3.3 ml) were stirred under a nitrogen atmosphere. NaOMe (14.7 ml, 4.6 M) was added before stirring at 120?C for 24 hours under reflux. After completion of the reaction, the reaction mixture was diluted with chloroform and subjected to extraction with NH.sub.4Cl and water. The organic layer was separated, concentrated in a vacuum, and purified to afford compound 2 as a solid (0.7 g, yield 87%, purity 99.7%).

(3) Synthesis of 2,7-dihydroxyspiro[fluorene-9,9-xanthene]

##STR00026##

[0153] In a two-neck flask equipped with a thermometer, a stirrer, and a condenser, compound (2 g, 5.096 mmol) was left under a nitrogen atmosphere. Glacial acetic acid (13 ml, 0.4 M) and 47% HBr (2.49 ml, 45.86 mmol) were added before stirring at 120? C. for 48 hours under reflux. After completion of the reaction, the reaction mixture was cooled to room temperature and subjected to extraction with chloroform and NaHCO.sub.3. The organic layer thus formed was separated, concentrated in a vacuum, and purified to afford compound 3 as a solid (1.8 g, yield 97%, purity 99.5%).

(4) Synthesis of 2,2-(spiro[fluorene-9,9-xanthene]-2,7-diylbis(oxy))diethanol (FX Synthesis)

##STR00027##

[0154] In a two-neck flask equipped with a thermometer, a stirrer, and a condenser, compound 3 (2 g, 5.488 mmol), dry DMF (13 ml), ethylene carbonate (0.887 ml, 12.07 mmol), and TBAF (0.1 ml, 0.1 mmol) were stirred together 150? C. for 3 hours under reflux. After completion of the reaction, the reaction mixture was cooled to room temperature and subjected to extraction with ethyl acetate and water. The organic layer thus formed was separated, concentrated in a vacuum, and purified to afford compound 4 as a solid (2.0 g, yield 83.3%, purity 99.3%).

[Experimental Example 1] .SUP.1.H NMR (in CDCl.SUB.3.) and HPLC Analysis of Compounds Synthesized in Example 1

[0155] .sup.1H NMR (in CDCl.sub.3) spectrum of the 2,7-dimethoxyspiro[fluorene-9,9-thioxanthene] synthesized in Example 1-(1) is as follows:

2,7-Dimethoxyspiro[fluorene-9,9-thioxanthene]

[0156] .sup.1H-NMR (500 MHz, CDCl.sub.3) : ?=7.60 (d, J=8.4 Hz, 2H), 7.42 (dd, J.sub.1=7.8 Hz, J.sub.2=1.2 Hz, 2H), 7.17 (td, J.sub.1=7.5 Hz, J.sub.2=1.4 Hz, 2H), 7.12 (d, J=2.4 Hz, 2H), 6.90-6.94 (m, 2H), 6.60 (dd, J.sub.1=8.0 Hz, J.sub.2=1.2 Hz, 2H), 3.74 (s, 6H.

[0157] .sup.1H NMR (in CDCl.sub.3) spectrum of the spiro[fluorene-9,9-thioxanthene]-2,7-diol synthesized in Example 1-(2) is as follows:

Spiro[fluorene-9,9-thioxanthene ]-2,7-diol

[0158] .sup.1H-NMR (500 MHz, CDCl.sub.3) : ?=7.56 (d, J=8.2 Hz, 2H), 7.41 (dd, J.sub.1=7.8 Hz, J.sub.2=1.0 Hz, 2H), 7.17 (td, J.sub.1=7.5 Hz, J.sub.2=1.3 Hz, 2H), 7.01 (d, J=2.3 Hz, 2H), 6.92 (td, J.sub.1=7.6 Hz, J.sub.2=1.3 Hz, 2H), 6.86 (dd, J.sub.1=8.2 Hz, J.sub.2=2.4 Hz, 2H), 6.60 (dd, J.sub.1=8.0 Hz, J.sub.2=1.0 Hz, 2H), 4.68 (s, 2H).

[0159] .sup.1H NMR spectrum (in CDCl.sub.3) of the 2,2-(spiro[fluorene-9,9-thioxanthene]-2,7-diylbis(oxy))diethanol (FTX) synthesized in Example 1-(3) is as follows:

2,2-(Spiro[fluorene-9,9-thioxanthene]-2,7-diylbis(oxy))bis(ethan-1-ol) [FTX]

[0160] .sup.1H-NMR (500 MHz, CDCl.sub.3) : ?=7.57 (d, J=8.4 Hz, 2H), 7.39 (dd, J.sub.1=7.8 Hz, J.sub.2=1.2 Hz, 2H), 7.15 (td, J.sub.1=7.5 Hz, J.sub.2=1.4 Hz, 2H), 7.10 (d, J=2.4 Hz, 2H), 6.87-6.91 (m, 2H), 6.57 (dd, J.sub.1=8.0 Hz, J.sub.2=1.2 Hz, 2H), 3.98-4.00 (m, 4H), 3.87-3.90 (m, 4H), 1.93 (t, J=6.2 Hz, 2H).

[0161] .sup.1H NMR (in CDCl.sub.3) spectrum of the 2,7-bis(2-hydroxyethoxy)spiro[fluorene-9,9-thioxanthene] 10,10-dioxide (FTXDO) synthesized in Example 1-(4) is as follows:

2,7-bis(2-hydroxyethoxy)spiro[fluorene-9,9-thioxanthene] 10,10-dioxide [FTXDO]

[0162] 1H-NMR (500 MHz, CDCl.sub.3) : ?=8.24-8.23 (d, J=7.9 Hz, 2H), 7.65-7.64 (m, 2H), 7.50-7.47 (t, J=7.6 Hz, 2H), 7.31-7.30 (t, J=7.7 Hz, 2H), 6.97-6.96 (m, 2H), 6.90 (s, 2H), 6.64-6.63 (d, J=8.1 Hz, 2H), 3.95-3.94 (m, 4H), 3.86-3.85 (m, 4H).

[0163] The synthesis method according to Example 1 was observed to guarantee high purity for the final product 2,7-bis(2-hydroxyethoxy)spiro[fluorene-9,9-thioxanthene] 10,10-dioxide and its intermediates

[Experimental Example 2] .SUP.1.H NMR (in CDCl.SUB.3.) and HPLC Analysis of Compounds Synthesized in Example 2

[0164] .sup.1H NMR (in CDCl.sub.3) spectrum of the 2,7-dibromospiro[fluorene-9,9-xanthene] synthesized in Example 2-(1) is as follows:

2,7-dibromospiro[fluorene-9,9-xanthene]

[0165] 1H-NMR (500 MHz, CDCl.sub.3): ?=7.64-7.62 (m, 2H), 7.51-7.49 (dd, J=8.1 Hz, 1.5 Hz, 2H), 7.24-7.23 (d, J=3.8 Hz, 6H), 6.84-6.81 (dt, J=8.1 Hz, 4.1 Hz, 2H), 6.39-6.37 (m, J=7.8 Hz, 2H).

[0166] .sup.1H NMR (in CDCl.sub.3) spectrum of the 2,7-dimethoxyspiro[fluorene-9,9-xanthene] synthesized in Example 2-(2) is as follows:

2,7-dimethoxyspiro [fluorene-9,9-xanthene]

[0167] 1H-NMR (500 MHz, CDCl.sub.3): ?=7.60-7.58 (d, J=8.4 Hz, 2H), 7.22-7.19 (m, 4H), 6.89-6.87 (dd, J=8.4 Hz, 2.4 Hz, 2H), 6.81-6.78 (ddd, J=8 Hz, 6.4 Hz, 2 Hz, 2H), 6.66 (d, J=2.4 Hz, 2H), 6.46-6.44 (m, 2H), 3.69 (s, 6H).

[0168] .sup.1H NMR (in CDCl.sub.3) spectrum of the 2,7-dihydroxyspiro[fluorene-9,9-xanthene] synthesized in Example 2-(3) is as follows:

2,7-dihydroxyspiro[fluorene-9,9-xanthene]

[0169] .sup.1H-NMR (500 MHz, CDCl.sub.3) : ?=7.57 (d, J=8.2 Hz, 2H), 7.22-7.23 (m, 4H), 6.82-6.86 (m, 4H), 6.61 (d, J=2.3 Hz, 2H), 6.49 (d, J=7.6 Hz, 2H), 4.57 (s, 2H).

[0170] .sup.1H-NMR (in CDCl.sub.3) spectrum and HPLC chromatogram of the 2,2-(spiro[fluorene-9,9-xanthene]-2,7-diylbis(oxy)) diethanol (FX) synthesized in Example 2-(4) is as follows :

2,2-(Spiro[fluorene-9,9-xanthene]-2,7-diylbis(oxy))bis(ethan-1-ol) [FX]

[0171] .sup.1H-NMR (500 MHz, CDCl.sub.3) : ?=7.60 (d, J=8.2 Hz, 2H), 7.17-7.22 (m, 4H), 6.90 (dd, J.sub.1=8.3 Hz, J.sub.2=2.4 Hz, 2H), 6.77-7.82 (m, 2H), 6.68 (d, J=2.3 Hz, 2H), 6.44 (dd, J.sub.1=7.8 Hz, J.sub.2=1.4 Hz, 2H), 3.95-3.97 (m, 4H), 3.84-3.88 (m, 4H), 1.90 (t, J=6.2 Hz, 2H).

[0172] The synthesis method according to Example 2 was observed to guarantee high purity for the final product 2,2-(spiro[fluorene-9,9-xanthene]-2,7-diylbis(oxy))diethanol and its intermediates.

[Experimental Example 3] Synthesis of Novel Xanthene Derivative Compound 3

[0173] 2,7-Bis(2-hydroxy)spiro[fluorene-9,9-thioxanthene] 10,10-dioxide was synthesized as illustrated in the following Reaction Scheme 3.

##STR00028##

[0174] In brief, 2,7-bis(2-hydroxyethoxy)spiro[fluorene-9,9-thioxanthene] 10,10-dioxide (112 mg, 0.22 mmol) was introduced into a two-neck flask equipped with a thermometer and a stirrer. DMSO (1 ml) was added before stirring. Then, KOH (74 mg, 1.32 mmol) was added, followed by stirring at 100? C. for 6 hours. After completion of the reaction, the temperature was decreased to room temperature. The reaction mixture was adjusted to a pH of 3, using 1N HCl before extraction with ethyl acetate and water. The organic layer thus formed was separated, concentrated in a vacuum, and purified to afford 2,7-bis(2-hydroxy)spiro[fluorene-9,9- thioxanthene] 10,10-dioxide (82 mg, yield 91.0%, purity 99.3%).

[Experimental Example 3] .SUP.1.H NMR (in CDCl.SUB.3.) and HPLC Analysis of Compounds Synthesized in Example 3

[0175] .sup.1H NMR (in CDCl.sub.3) spectrum of the 2,7-bis(2-hydroxy)spiro[fluorene-9,9-thioxanthene] 10,10-dioxide synthesized in Example 3 is as follows:

2,7-bis(2-hydroxy)spiro[fluorene-9,9-thioxanthene] 10,10-dioxide [FTXDO-OH]

[0176] .sup.1H-NMR (500 MHz, CDCl.sub.3): ?=5.02 (s, 2 H), 6.66 (d, J=8.24 Hz, 2 H), 6.75 (s, 2 H), 6.90 (d, J=2.44 Hz, 2 H), 7.32 (br. s., 1 H), 7.50 (s, 1 H), 7.60 (d, J=8.39 Hz, 2 H), 8.22 (d, J=8.09 Hz, 2 H).

[0177] The synthesis method according to Example 3 was observed to guarantee high purity for the final product 2,7-bis(2-hydroxy)spiro[fluorene-9,9-thioxanthene] 10,10-dioxide.

[Example 4] Synthesis of Polyurethane With Novel Xanthene-Based Monomer

[0178] ##STR00029## ##STR00030##

[0179] To a solution of 1.0 equiv. diol monomer compound in 0.46 M anhydrous DMAc was added 1.5 equiv. isophorone diisocyanate (IPDI), together with 4 mol % dibutyltin dilaurate (DBTDL) as a catalyst. The mixture was stirred at 80? C. under an argon atmosphere. After 3 hours, anhydrous ethylene glycol (1.5 equiv.) was added as a chain extender to the solution. The mixture was stirred at 80? C. for 3 hours under an argon atmosphere. The reaction mixture was cooled to room temperature and added with water to give a primary product as a precipitate. This product was dissolved in THE and precipitated again in water. The remaining solvent was removed by drying at room temperature in a vacuum to afford the final product.

(1) Synthesis of PU-FBPE (PU-1)

[0180] PU-FBPE was synthesized from the conventional high-refractive index material 4,4-(9-fluorenylidene)bis(2-phenoxyethanol) [FBPE] (4.00 g, 9.12 mmol) according to the general reaction scheme. The product was obtained as a white solid.

(2) Synthesis of PU-FX (PU-2)

[0181] PU-FX was synthesized from 2,2-(spiro[fluorene-9,9-xanthene]-2,7-diylbis(oxy)) diethanol [FX] (2.06 g, 4.56 mmol) according to the general reaction scheme. The product was obtained as an off-white solid.

(3) Synthesis of PU-FTX (PU-3)

[0182] PU-FTX was synthesized from 2,2-(spiro[fluorene-9,9-thioxanthene]-2,7-diylbis(oxy))diethanol [FTX] (2.14 g, 4.56 mmol) according to the general reaction scheme. The product was obtained as a white solid.

(4) Synthesis of PU-FTXDO (PU-4)

[0183] PU-FTXDO was synthesized from 2,7-bis(2-hydroxyethoxy)spiro[fluorene-9,9-thioxanthene] 10,10-dioxide [FTXDO] (2.28 g, 4.56 mmol) according to the general reaction scheme. The product was obtained as an off-white solid.

[Experimental Example 4] Characterization of Polyurethane Synthesized in Example 4

4-1. Analysis for Refractive Index of Synthesized Polyurethane

[0184] The polyurethanes PU-1 to PU-4 synthesized in Example 4 were analyzed for refractive index.

[0185] For use in measuring refractive indices, sample solutions in DMAc (dimethylacetamide) were prepared into films 55 ?m thick on Si wafer by a spin coating method. Refractive indices of the films were measured using Spectroscopic Ellipsometer (Nano-View, SeMG-100). The measurements are depicted in FIG. 3.

[0186] As shown in FIG. 3, compared to PU-1 prepared using the conventional high-refractive index material 4,4-(9-fluorenylidene)bis(2-phenoxyethanol) [FBPE] , the polyurethane materials PU-2 to PU-4 prepared from the high-refractive index monomers 2,2-(spiro[fluorene-9,9-xanthene]-2,7-diylbis(oxy)) diethanol [FX], 2,2-(spiro[fluorene-9,9-thioxanthene]-2,7-diylbis(oxy))diethanol [FTX], and 2,7-bis(2-hydroxyethoxy)spiro[fluorene-9,9-thioxanthene] 10,10-dioxide [FTXDO], which were all newly synthesized in the present disclosure, were observed to have improved refractive indices.

4-2. Analysis for Transmittance of Synthesized Polyurethane

[0187] The polyurethanes PU-1 to PU-4 synthesized in Example 4 were analyzed for transmittance.

[0188] For use in measuring transmittance, sample solutions in DMAc (dimethylacetamide) were prepared into films 55 ?m thick on slide glass by a spin coating method. Transmittance of the films was measured using UV-1800 spectrophotometer (Shimadzu).

[0189] The measurements are depicted in FIG. 4.

[0190] As shown in FIG. 4, the novel polyurethane materials PU-2 to PU-4 synthesized in Example 4 of the present disclosure were all found to have excellent transmittance as in the polyurethane material PU-1 made using conventional monomers.

4-3. Analysis for Thermal Properties of Synthesized Polyurethane

[0191] To analyze the thermal properties of the polyurethane materials PU-1 to PU-4 synthesized in Example 4, differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were performed. The decomposition temperature (Td) and glass transition temperature (Tg) along with other measured analysis results are depicted in FIG. 5.

[0192] As shown in FIG. 5, the novel polyurethane materials PU-2 to PU-4 synthesized in Example 4 of the present disclosure all showed similar or even higher decomposition temperatures (Td) compared to the polyurethane material PU-1 made using conventional monomers, indicating superior thermal stability. Moreover, when compared to PU-1, there was a significant increase in the glass transition temperature, indicating excellent heat resistance.

4-4. Analysis for Molecular Weight of Synthesized Polyurethane

[0193] Furthermore, the polyurethane materials PU-1 to PU-4 synthesized in Example 4 were analyzed for molecular weight, and the results are summarized in Table 1.

TABLE-US-00001 TABLE 1 Polyurethane Mn Mw PDI PU-1 16.3K 32.5K 1.99 PU-2 18.3K 36.9K 2.01 PU-3 52.2K 96.3K 1.92 PU-4 33.0K 66.8K 2.01 Mn: number averaged molecular weight Mw: weight averaged molecular weight PDI: polydispersity index

[Example 5] Synthesis of Polycarbonate with Novel Xanthene-Based Monomer

[0194] ##STR00031##

[0195] A solution of diol monomer compound (1.0 equiv.) and pyridine (3.9 equiv.) in DCM was cooled to 0? C. and slowly added with triphosgene (0.4 equiv.) over 2 hours while stirring. The mixture was stirred at 0? C. for 30 minutes and at room temperature for 5 hours. The reaction mixture was washed with water and the organic layer was concentrated to give a primary solid product. This solid product was precipitated in a mixture of isopropanol and water (9:1). Drying at room temperature in a vacuum removed the remaining solvent to afford the final products PC-1 to PC-4.

(1) Synthesis of PC-FBPE (PC-1)

[0196] PC-FBPE was synthesized from the conventional high-refractive index monomer 4,4-(9-fluorenylidene)bis(2-phenoxyethanol) [FBPE] (1.00 g, 2.28 mmol) and DCM (0.2 M) according to the general reaction scheme. The product was obtained as a white solid.

(2) Synthesis of PC-FX (PC-2)

[0197] PC-FX was synthesized from 2,2-(spiro[fluorene-9,9-xanthene]-2,7-diylbis(oxy)) diethanol [FX] (1.00 g, 2.20 mmol) and DCM (0.05M) according to the general reaction scheme. The product was obtained as a white solid.

(3) Synthesis of PC-FTX (PC-3)

[0198] PC-FTX was synthesized from 2,2-(spiro[fluorene-9,9-thioxanthene]-2,7-diylbis(oxy))diethanol [FTX] (1.00 g, 2.12 mmol) and DCM (0.05M) according to the general reaction scheme. The product was obtained as a white solid.

(4) Synthesis of PC-FTXDO (PC-4)

[0199] PC-FTXDO was synthesized from FTXDO (1.00 g, 1.99 mmol) and DCM (0.17 M) according to the general reaction scheme. The product was obtained as a white solid.

[Experimental Example 5] Characterization of Polycarbonate Synthesized in Example 5

5-1. Analysis for Refractive Index of Synthesized Polycarbonate

[0200] The polycarbonate PC-1 to PC-4 synthesized in Example 5 were analyzed for refractive index. The results are depicted in FIG. 6.

[0201] As shown in FIG. 6, compared to the polycarbonate PC-1 prepared using the conventional high-refractive index 4,4-(9-fluorenylidene)bis(2-phenoxyethanol) material [FBPE], the polycarbonates PC-2 to PU-4 prepared from the high-refractive index monomers 2,2-(spiro[fluorene-9,9-xanthene]-2,7-diylbis(oxy)) diethanol [FX], 2,2-(spiro[fluorene-9,9-thioxanthene]-2,7-diylbis(oxy))diethanol [FTX], and 2,7-bis(2-hydroxyethoxy)spiro[fluorene-9,9-thioxanthene] 10,10-dioxide [FTXDO], which were all newly synthesized in the present disclosure, were observed to have improved refractive indices.

5-2. Analysis for Transmittance of Synthesized Polycarbonate

[0202] The polycarbonates PC-1 to PC-4 synthesized in Example 4 were analyzed for transmittance in the same manner as in Experimental Example 4-2.

[0203] The measurements are depicted in FIG. 7.

[0204] As shown in FIG. 7, the novel polycarbonate materials PC-2 to PC-4 synthesized in Example 5 of the present disclosure were all found to have excellent transmittance as in the polycarbonate material PC-1 made using conventional monomers.

5-3. Analysis for Thermal Properties of Synthesized Polycarbonate

[0205] To analyze the thermal properties of the polycarbonate materials PC-1 to PC-4 synthesized in Example 5, differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were performed. The decomposition temperature (Td) and glass transition temperature (Tg) along with other measured analysis results are depicted in FIG. 8.

[0206] As shown in FIG. 8, the novel polycarbonate materials PC-2 to PC-4 synthesized in Example 5 of the present disclosure all showed similar or even higher decomposition temperatures (Td) compared to the polycarbonate material PC-1 made using conventional monomers, indicating superior thermal stability. Moreover, when compared to PC-1, there was a significant increase in the glass transition temperature, indicating excellent heat resistance.

5-4. Analysis for Molecular Weight of Synthesized Polycarbonate

[0207] The results are summarized in Table 2.

TABLE-US-00002 TABLE 2 Polycarbonate Mn Mw PDI PC-1 15.5K 30.8K 2.20 PC-2 10.9K 40.8K 3.70 PC-3 6.8K 31.4K 4.50 PC-4 8.2K 29.6K 3.60 Mn: number averaged molecular weight Mw: weight averaged molecular weight PDI: polydispersity index

[0208] While the embodiments of the present disclosure and their advantages have been described in detail above, it should be understood that various changes, substitutions and alterations may be made herein without departing from the scope of the disclosure.